Microwaveable popcorn (sometimes referred to as microwave popcorn) has become a very popular consumer item. In general, the form of product obtained by the consumer comprises unpopped popcorn enclosed within a disposable container, such as a paper or fiberboard container. In some instances microwave susceptors are provided within the arrangement, to facilitate collection of microwave energy and heat transfer to the product. The product is typically used by placing the container, with the unpopped popcorn therein, inside a microwave oven. After exposure to microwave energy in a conventional microwave oven for about 1-5 minutes, about 95% of the popcorn generally converts to its popped form, for consumption. Microwave popcorn arrangements are described, for example, in U.S. Pat. Nos. 5,044,777; 4,548,826; 4,691,374; and, 4,450,180, the disclosures of which are incorporated herein by reference.
In general, for many microwave popcorn products, the popcorn is enclosed in the container in the presence of an oil or fat, to facilitate the popping process. The oil or fat operates as a heat sink for energy during the operation, and facilitates retention of heat within the container to help the popcorn pop to its fullest.
Many efforts have been directed toward providing flavorings on the popcorn. Butter, salt or similar flavorings, for example, are sometimes included within the fat/oil in the bag, to transfer flavoring to the popcorn as it is popped.
Sweetened popcorn products have enjoyed a substantial popularity. For example, caramel popcorn is a popular product. In general., many products for sweetening microwaveable popcorn are provided in a multi-step form. In such a flavoring process, the popcorn is first popped, in the absence of the sweetened flavoring. The sweetened flavoring, appropriately warmed, is then spread over the popcorn, usually with intermittent shaking, before consumption. That is, the popcorn is not provided in the presence of the sweetened coating until after the popcorn has been popped. Such processes are referred to herein as multi-step, because of the separate steps for the consumer of cooking the popcorn and providing the sweetened coating on the cooked popcorn.
A principal reason why such sweetening processes have generally been utilized for microwaveable popcorn is that sugars present in sweetened flavorings tend to burn in conventional microwaveable systems, as the popcorn is popped. Thus, if a conventional caramel flavoring is provided in the container with the unpopped popcorn, and the container of unpopped popcorn, in contact with the caramel flavoring, is exposed to microwave energy, in general there is a tendency for the sugars in the flavoring to scorch, burn or decompose to an undesirable extent during the process, before the popping of the popcorn is completed. This leads to an undesirable taste, texture and/or aroma, for the consumer.
It has been widely recognized that it would be desireable to develop a system for sweetening microwave popcorn, whereby the sweetened flavoring could be provided in contact with the unpopped popcorn in the container, and be exposed to the microwave energy during the popping process. In this way, the consumer would only need to place the product in the microwave oven, for the appropriate period of time, and then open the product to consume the sweetened popcorn.
One approach for developing a microwaveable glazed popcorn, that is popped in the presence of a sweet. (sugar-containing) mixture, is described in Belleson et al., U.S. Pat. No. 4,751,090. According to the reference, water is utilized in the coating composition, to slow down the temperature rise of the coating during exposure to microwave energy.